A new study claims that women care what side of the bed they sleep on, but men usually don't, so women often get their way. Of course, the reason is evolution: "Men are naturally designed to want to protect their female partner and that means, more often than not, they will allow her to call the shots over ‘disputed territories' like preference for a certain side of the bed." It's true — in prehistoric times, men who allowed women to pick which side of the cave they slept on were rewarded with sex and therefore offspring. Men who insisted on picking a side themselves were usually eaten by dire wolves.